	ORG 0000H
	LJMP MAIN
	ORG 0003H
	LJMP INT
	ORG 0100H
MAIN:
	CLR P1.0
	SETB IT0 //边沿触发
	SETB EX0 //外部中断允许
	SETB EA
	SJMP $
INT:
	CLR EA
	CPL P1.0
	SETB EA
	RETI
	END